After a little investigating (Google..) I found this brief explanation:

As early as 1914, Japanese cartoonists were experimenting with animation. Previously, Japanese cartoonists, influenced by the west, were producing serial newspaper comics. These evolved into full length manga. The first world wide animation success was Momotaro (1918). Several short films and shows followed, but anime and manga fans everywhere really owe their thanks to one man: Osamu Tezuka.

Tezuka revolutionized manga and anime. His characters were energetic and emotional. His stories lasted for hundreds of pages and told the story with his active pictures as well as his words. His character designs were highly influenced by Disney. The huge eyes are the most noticeable feature. The design allowed for a wide range of emotions. Tezuka's black and white anime Tetsuwan Atom (1958), or Astro Boy in English, was the first regular anime to be have a formal set of characters. It centered around a robot boy who has an atomic heart. He is rejected by his creator and sold to a circus. Though the teaching of Dr. Elfun, the robot boy fights against evil for the protection of all mankind. This anime was adapted from his manga of the same name.

This is kind of an odd question -- it depends on what you mean by "anime". Do you mean any kind of animated cartoon, or do you mean any Japanese animation, or do you mean Japanese animation like the stuff that American anime fans watch today?

Yudan Taiteki wrote:This is kind of an odd question -- it depends on what you mean by "anime". Do you mean any kind of animated cartoon, or do you mean any Japanese animation, or do you mean Japanese animation like the stuff that American anime fans watch today?

I must agree. You leave lots of room for interpretation in your question. After reading the op, I was thinking all modern animation (tv, film, or flash) can be traced back to Disney.